About CalculatorPOP
I'm Sroush, and I build, test, and fact-check every calculator on this site myself before it goes live. CalculatorPOP is a one-person project, run from Norway, with no company behind it and nothing hidden behind a sign-up form.
Why This Site Exists
CalculatorPOP started as a handful of calculators I built for myself, because most of what I found online was either buried under ads that pushed the result off the screen, or it gave a number without saying where the number came from. Neither is useful if you want to trust the answer.
My background is finance, where the entire job is being careful about how a figure is defined and where it quietly misleads you. That is the habit this site runs on. Every calculator sits next to an article that writes out the formula, names the source, and says plainly what the result cannot tell you.
How Each Calculator Gets Checked
Start from an official or primary source for the formula and ranges, such as the CDC, WHO, NHLBI, NHS, a peer-reviewed paper, or a manufacturer specification. Figures are confirmed at the source rather than copied from another website.
Build the calculator, then check the math by hand across unit conversions and boundary values, not just the first example that happened to work.
Write the article beside it, covering what the result means, what it leaves out, and when to treat it with caution, with sources listed at the bottom.
Revisit the page when guidance changes. Health and nutrition recommendations are updated periodically, and correcting a page beats leaving stale numbers live.
If a calculator saved you time, sharing it is the easiest way to say thanks.
CalculatorPOP is free, ad-supported, and built by one person who checks the math by hand. Passing a link to someone who needs it helps more than you would think.